src/mesa/math/m_xform.h

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.3
   4  *
   5  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 #ifndef _M_XFORM_H
  27 #define _M_XFORM_H
  28
  29
  30 #include "main/glheader.h"
  31 #include "main/config.h"
  32 #include "math/m_vector.h"
  33 #include "math/m_matrix.h"
  34
  35 #ifdef USE_X86_ASM
  36 #define _XFORMAPI _ASMAPI
  37 #define _XFORMAPIP _ASMAPIP
  38 #else
  39 #define _XFORMAPI
  40 #define _XFORMAPIP *
  41 #endif
  42
  43
  44 extern void
  45 _math_init_transformation(void);
  46
  47
  48 /* KW: Clip functions now do projective divide as well.  The projected
  49  * coordinates are very useful to us because they let us cull
  50  * backfaces and eliminate vertices from lighting, fogging, etc
  51  * calculations.  Despite the fact that this divide could be done one
  52  * day in hardware, we would still have a reason to want to do it here
  53  * as long as those other calculations remain in software.
  54  *
  55  * Clipping is a convenient place to do the divide on x86 as it should be
  56  * possible to overlap with integer outcode calculations.
  57  *
  58  * There are two cases where we wouldn't want to do the divide in cliptest:
  59  *    - When we aren't clipping.  We still might want to cull backfaces
  60  *      so the divide should be done elsewhere.  This currently never
  61  *      happens.
  62  *
  63  *    - When culling isn't likely to help us, such as when the GL culling
  64  *      is disabled and we not lighting or are only lighting
  65  *      one-sided.  In this situation, backface determination provides
  66  *      us with no useful information.  A tricky case to detect is when
  67  *      all input data is already culled, although hopefully the
  68  *      application wouldn't turn on culling in such cases.
  69  *
  70  * We supply a buffer to hold the [x/w,y/w,z/w,1/w] values which
  71  * are the result of the projection.  This is only used in the
  72  * 4-vector case - in other cases, we just use the clip coordinates
  73  * as the projected coordinates - they are identical.
  74  *
  75  * This is doubly convenient because it means the Win[] array is now
  76  * of the same stride as all the others, so I can now turn map_vertices
  77  * into a straight-forward matrix transformation, with asm acceleration
  78  * automatically available.
  79  */
  80
  81 /* Vertex buffer clipping flags
  82  */
  83 #define CLIP_RIGHT_SHIFT        0
  84 #define CLIP_LEFT_SHIFT         1
  85 #define CLIP_TOP_SHIFT          2
  86 #define CLIP_BOTTOM_SHIFT       3
  87 #define CLIP_NEAR_SHIFT         4
  88 #define CLIP_FAR_SHIFT          5
  89
  90 #define CLIP_RIGHT_BIT   0x01
  91 #define CLIP_LEFT_BIT    0x02
  92 #define CLIP_TOP_BIT     0x04
  93 #define CLIP_BOTTOM_BIT  0x08
  94 #define CLIP_NEAR_BIT    0x10
  95 #define CLIP_FAR_BIT     0x20
  96 #define CLIP_USER_BIT    0x40
  97 #define CLIP_CULL_BIT    0x80
  98 #define CLIP_FRUSTUM_BITS    0x3f
  99
 100
 101 typedef GLvector4f * (_XFORMAPIP clip_func)( GLvector4f *vClip,
 102                                              GLvector4f *vProj,
 103                                              GLubyte clipMask[],
 104                                              GLubyte *orMask,
 105                                              GLubyte *andMask );
 106
 107 typedef void (*dotprod_func)( GLfloat *out,
 108                               GLuint out_stride,
 109                               CONST GLvector4f *coord_vec,
 110                               CONST GLfloat plane[4] );
 111
 112 typedef void (*vec_copy_func)( GLvector4f *to,
 113                                CONST GLvector4f *from );
 114
 115
 116
 117 /*
 118  * Functions for transformation of normals in the VB.
 119  */
 120 typedef void (_NORMAPIP normal_func)( CONST GLmatrix *mat,
 121                                       GLfloat scale,
 122                                       CONST GLvector4f *in,
 123                                       CONST GLfloat lengths[],
 124                                       GLvector4f *dest );
 125
 126
 127 /* Flags for selecting a normal transformation function.
 128  */
 129 #define NORM_RESCALE   0x1              /* apply the scale factor */
 130 #define NORM_NORMALIZE 0x2              /* normalize */
 131 #define NORM_TRANSFORM 0x4              /* apply the transformation matrix */
 132 #define NORM_TRANSFORM_NO_ROT 0x8       /* apply the transformation matrix */
 133
 134
 135
 136
 137 /* KW: New versions of the transform function allow a mask array
 138  *     specifying that individual vector transform should be skipped
 139  *     when the mask byte is zero.  This is always present as a
 140  *     parameter, to allow a unified interface.
 141  */
 142 typedef void (_XFORMAPIP transform_func)( GLvector4f *to_vec,
 143                                           CONST GLfloat m[16],
 144                                           CONST GLvector4f *from_vec );
 145
 146
 147 extern dotprod_func  _mesa_dotprod_tab[5];
 148 extern vec_copy_func _mesa_copy_tab[0x10];
 149 extern vec_copy_func _mesa_copy_clean_tab[5];
 150 extern clip_func     _mesa_clip_tab[5];
 151 extern clip_func     _mesa_clip_np_tab[5];
 152 extern normal_func   _mesa_normal_tab[0xf];
 153
 154 /* Use of 2 layers of linked 1-dimensional arrays to reduce
 155  * cost of lookup.
 156  */
 157 extern transform_func *_mesa_transform_tab[5];
 158
 159
 160
 161 #define TransformRaw( to, mat, from ) \
 162    ( _mesa_transform_tab[(from)->size][(mat)->type]( to, (mat)->m, from ), \
 163      (to) )
 164
 165
 166 #endif